Equity Investments (Distributions From Equity Investments) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Schedule of Equity Method Investments [Line Items]
Distributions from equity investments	$ 2,140	$ 2,250	$ 3,540	$ 5,050
Deepwater Gateway, L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Distributions from equity investments	1,700	1,750	2,700	3,750
Independence Hub, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Distributions from equity investments	$ 440	$ 500	$ 840	$ 1,300